“It is credible enough on the face of it. It seems clear that—unless he is a very good actor indeed—he genuinely believes it was Ackroyd himself who was the victim of blackmail. If so, he knows nothing at all about the Mrs. Ferrars business.”

“Then in that case—who——”

Précisément! Who? But our visit to M. Hammond will accomplish one purpose. It will either clear Parker completely or else——”

“Well?”

“I fall into the bad habit of leaving my sentences unfinished this morning,” said Poirot apologetically. “You must bear with me.”

“By the way,” I said, rather sheepishly, “I’ve got a confession to make. I’m afraid I have inadvertently let out something about that ring.”

“What ring?”

“The ring you found in the goldfish pond.”

“Ah! yes,” said Poirot, smiling broadly.

“I hope you’re not annoyed? It was very careless of me.”